Rolling mill material handling system

Abstract: A rolling mill material handling system includes a cooling bed (20) and an associated laying head and cooling conveyor (38). Hot rolled products may be cut into segments which are shifted laterally onto the cooling bed. Alternatively, the hot rolled products may be directed longitudinally in undivided lengths past the cooling bed to the laying head (32) where they are formed into rings and deposited on the cooling conveyor.

Description: This invention relates generally to continuous hot rolling mills of the type which produce so called "long products" (e.g. rods, bars and the like), and is concerned in particular with an improved system for handling such products as they emerge from the mill. In a typical conventional mill installation where for example billets are being rolled continuously into round bars, the finished product is usually subdivided into shorter segments as it emerges from the mill. These product segments are then brought to rest and shifted laterally onto the receiving end of a cooling bed. The product segments undergo cooling as they progress laterally across the cooling bed. Upon arriving at the delivery end of the bed, the coiled product segments are further subdivided into shorter customer lengths prior to being bundled. Problems are often encountered in the shearing and/or bundling of the product segments leaving the delivery end of the cooling bed, causing the cooling bed to become rapidly filled. This in turn necessitates a shut down of the entire mill. A primary objective of the present invention is to provide an improved material handling system which includes an overflow outlet for the cooling bed in the event that shearing and bundling problems are encountered. In a preferred embodiment of the invention, the material handling system includes a shear positioned along the delivery path leading from the mill. The shear is operable selectively in either a first mode in which it subdivides the finished product into segments, or a second mode permitting the product to continue along the delivery path in an undivided state. A cooling bed is positioned along the delivery path downstream from the shear. A run on table is operable selectively in either a first mode transferring product segments received from the shear onto the cooling bed, or a second mode allowing individual product to continue along the delivery path past the cooling bed. A laying head is positioned along the delivery path downstream from the cooling bed. The laying head forms undivided product bypassing the cooling bed into rings which are deposited on a cooling conveyor in the form of overlapping non-concentric rings. The rings are cooled on the conveyor before they are gathered into coils at a reforming station at the delivery end of the conveyor. Preferably, driven pinch roll units are strategically positioned along the rolling line to achieve braking and/or to ensure unimpeded progress of the product through the various handling stages. Optionally, a rolling unit can be located between the cooling bed and the laying head to further roll the product into smaller diameter rods and the like. These and other objects, features and advantages will be described in greater detail with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic plan view of a material handling system according to one embodiment of the invention; and Figure 2 is a diagrammatic partial plan view showing an alternative embodiment. Referring initially to Figure 1, the last roll stand of a continuous hot rolling mill is depicted at (10). Hot rolled long products, typically round bars or the like, emerge from roll stand (10) along a delivery path (12). A shear (14) is located along the delivery path (12). The shear may comprise any one of several known conventional designs of the type shown for example in US Patent No. 3,851,556 (Sieurin) and US Patent No. 3,834,260 (Sieurin et al). The shear operates to subdivide the finished product emerging from roll stand (10) into shorter segments which proceed alternatively either along delivery path (12) or a parallel path (12'). Typically, one or more water cooling boxes (16) will be arranged between the shear (14) and the roll stand (10) in order to lower the temperature of the product by surface quenching, and a driven pinch roll unit (18) will be provided between the last water box and the shear in order to ensure that the product continues to move along the delivery path (12) after the tail end has cleared the last roll stand (10). The pinch roll unit (18) can again be of conventional design, as shown for example in US Patent No. 4,413,494 (Gilvar et al). The shear (14) is operable selectively between a first mode subdividing the finished product into segments as described above, and a second mode which permits the finished product to continue along path (12) in an undivided state. A cooling bed (20) extends laterally from the delivery paths (12,12') at a location downstream from the shear (14). A run in table (22) is operatively positioned between the delivery paths (12,12') and the receiving end of the cooling bed. Additional pinch roll units (24,26) are positioned respectively along paths (12,12') between the shear (14) and the run in table (22). The pinch roll units (24,26) operate to decelerate product segments travelling along paths (12,12'), thereby allowing them to slide to a halt within the operative length of the run in table (22). The run in table may again be of known design, for example as shown in U.S. Patent No. 4,809,530 (Wilson). The run in table serves to transfer product segments received along paths (12,12') onto the receiving end of the cooling bed (20) where the segments progress laterally in the direction indicated schematically by arrow (28) to the delivery end of the bed. While moving laterally across the cooling bed, the product segments undergo further cooling in ambient air. As the product segments arrive at the delivery end of the cooling bed, they are received and further subdivided into customer lengths before being bundled in readiness for storage and subsequent shipment. Equipment employed to receive, further subdivide and bundle the product segments is indicated generally at (30). Typical examples of such equipment can be found in US Patent No. 3,718,062 (Gilvar), US Patent No. 4,006,828 (Hill), US Patent No. 3,823,812 (Sieurin) and US Patent No. 3,497,084 (Murrah). A laying head (32) is positioned along path (12) at a location following the cooling bed (20). Preferably, a pinch roll unit (34) is located between the laying head and the cooling bed in order to ensure that product received along path (12) is reliably propelled into and through the laying head. The laying head operates to form product into a continuous series of rings (36) which are received on a cooling conveyor (38). The conveyor transports the rings in an overlapping non-concentric form to a reforming station (40). A reforming apparatus (42) at station (40) serves to gather the rings into coils (44) which are transported away from station (40) on a conveyor 46. Typical examples of a laying head and cooling conveyor are provided in US Patent No. 4,546,957 (Jalil et al) and US Patent No. 5,121,902 (Jalil et al), and an example of a reforming apparatus is shown in US Patent No. 4,251,037 (Puchovosky). When the shear (14) is operating to subdivide the finished product into shorter segments, the segments are slowed by the pinch roll units (24,26) and brought to a stop within the operative range of the run in table (22). The run in table then operates to laterally transfer the segments onto the cooling bed (20) for further processing away from the delivery paths (12,12'). In this mode of operation, the laying head (32) and its associated material handling components are inoperative. In the event, however, that difficulties are encountered with the material handling equipment (30), resulting in the cooling bed (20) becoming rapidly filled with product segments, the shear (14) may be adjusted to an alternative mode allowing the finished product to proceed along path (12) in an undivided state. Under these conditions, the run in table (22) is also operatively adjusted to an alternative mode allowing the undivided product to continue past the cooling bed (20) along path (12). The pinch roll unit (34) is then operated to continue propelling the undivided product into and through the laying head (30) where it is formed into rings (36) for deposit on the cooling conveyor (38). As described above, these rings are ultimately gathered into coils at station (40). It will thus be seen that with the present invention, an overflow capacity is provided for the cooling bed (20). This overflow capacity ensures that in the event of a malfunction of the equipment (30), the mill can continue in operation with the finished product being alternatively directed past the cooling bed. An alternative embodiment of the invention is disclosed in Figure 2. Here, a short rolling block (48) of the type depicted for example in US Patent No. 4,537,055 (Woodrow et al) is located between the cooling bed (20) and the laying head (32). Preferably, an additional water cooling box (50) is interposed between the delivery end of the block (48) and the pinch roll unit (34) preceding the laying head. With this arrangement, undivided product such as larger diameter bars may be further rolled into smaller products such as rods. This additionally increases the options available to the mill owner. It will be understood, of course, that in addition to providing overflow capacity, the laying head (32) and cooling conveyor (38) may be operated with or without an associated additional rolling block (48) to handle different types of products irrespective of whether the cooling bed is temporarily filled as a result of a malfunction of the equipment (30).

Claims: A material handling system for hot rolled long products emerging longitudinally along a delivery path (12) from a continuous hot rolling mill (10), said system having shear means (14) along said delivery path, said shear means being operable selectively between a first mode subdividing said product into segments and a second mode permitting said product to continue along said path in an undivided state, a cooling bed (20) positioned alongside said path at a location following said shear means, and transfer means (22) operable selectively between a first mode transferring product segments received from said shear onto said cooling bed, and a second mode permitting longer undivided product lengths to continue along said delivery path past said cooling bed, wherein a laying bead (32) is positioned along said path at a location following said transfer means, said laying head being operative to form said undivided product lengths into a continuous series of rings (36), a conveyor (38) is arranged to receive said rings from said laying head and for transporting said rings to a reforming station (40), and means (42) are provided at said reforming station for gathering said rings into coils. The material handling system of claim 1 further characterized by decelerating means (24,26) positioned between said shear means and said transfer means for slowing said product segments. The material handling system of claim 2 further characterized by said decelerating means comprising at least one pinch roll unit (24). The material handling system of claim 1 further characterized by means (34) for propelling products into said laying head. The material handling system of claim 4 further characterized in that said means for propelling comprises a pinch roll unit. The material handling system of claim 1 further characterized by switch means operating in conjunction with said shear means to direct successive product segments alternatively along said delivery path and an adjacent path parallel thereto. The material handling system of claim 1 further characterized by said cooling bed having a receiving end underlying said delivery path and a delivery end remotely disposed laterally therefrom, and wherein said transfer means is operable to deposit said product segments onto said receiving end. The material handling system of claim 1 further characterized by means associated with said conveyor for coiling the rings being transported to said reforming station. The material handling system of claim 1 further characterized by means (16) arranged along said delivery path for cooling said product in advance of said shear means. The material handling system of claim 9 further characterized by means (18) interposed between said cooling means and said shear means for propelling said product along said delivery path. The material handling system of claim 10 further characterized in that said propelling means comprises a pinch roll unit. The material handling system of claim 1 further characterized by rolling means (48) between said transfer means and said laying head for further reducing the cross sectional area of said product. A process of operating a material handling system according to claim 1, for handling a hot rolled long product emerging continuously from a hot rolling mill (10) wherein the product is divided into segments by a shear means (14) and deposited onto a cooling bed (20), characterised by inactivating said shear means and directing the undivided product along a delivery path to alternative cooling means (38) in the event that the cooling bed (20) becomes overloaded or malfunctions. A process as claimed in claim 13 wherein said undivided product is cut into segments prior to deposition onto said alternative cooling means.

Inventors: SHORE TERENCE MICHAEL, SHORE, TERENCE MICHAEL
Applicants: MORGAN CONSTRUCTION CO, MORGAN CONSTRUCTION COMPANY
Application year: 1994
Main classification: B21B1
IPC codes: B21B15, B21C47, B21B1, B21B43, B21B39, B21B41, B65H54, B21B45